Label-Free Bimetallic In Situ Grown 3D Nickel Foam Supported NH2-MIL-88B(Fe2Co)-MOF based Impedimetric Immunosensor for the Detection of Cardiac Troponin I.

In this study, a simple and competent metal-organic framework (MOF) based nickel foam (NF) supported 3D immunosensor (Ab-NH2-MIL-88B(Fe2Co)-MOF/NF) was constructed and utilized for the specific recognition of the biomarker cardiac troponin (I). In the present work, the biosensor fabrication was progressed through the modification of the NF substrate with MOF material (NH2-MIL-88B(Fe2Co)-MOF) to enable amine functionalized electrode. This amine functionalized NF electrodes (NH2-MIL-88B(Fe2Co)-MOF/NF) were then bio-interfaced with anti-cTnI antibodies and ended up as Ab-NH2-MIL-88B(Fe2Co)-MOF/NF electrodes. Analytical executions of the constructed bio-electrode were investigated for the quantitative analysis of cTnI in both buffered and serum solutions. Then, the electrochemical studies were carried out using the electrochemical impedance spectroscopy (EIS) method by monitoring changes concerning the charge transfer resistance (Rct) characteristics. The limit of detection (LOD) of Ab-NH2-MIL-88B(Fe2Co)-MOF/NF immunosensor was achieved to be 13 fg/ml with great specificity. This kind of immunosensor imparts a new platform for the construction and application of MOF-hybrid 3D electrode materials with enhanced electrochemical behavior in cTnI sensing for the first time.